Liquid fuel burner



March 29, 1932. F. F. NEUMANN LI UID FUEL BURNER Filed April 24; 19:51

3 Sheets-Sheet March 29, 1932. NE AN'N' 1,851,919

LIQUID FUEL BURNER Filed April 24, 1931 3 sheets she et 2 March 29,1932. F F, E 1,851,919-

LIQUID FUEL BURNER FiIed'April 24, 1 951 3 Sheets-Sheet 5 Irwezaor:

b 2M 6% f 4 9 Patented Mar. ?.9, 1932 UNITED STATES PATENT OFFICEFREDERICK IL, NEUMANN, OF WEST HARTFORD, EONNECTICUT, ASSIGNOR TO THE 1SILENT GLOW OIL BURNER CORPORATION,

RATION OF CONNECTICUT F HARTFORD, CONNECTICUT, A CORPO-' LIQUID FUELBURNER.

Application filed April 24,

This invention relates to liquid fuel burners of the type supplied withoil or other hydrocarbon fuel in liquid form, the fuel being vaporizedin the burner and burned with a l suitable mixture of air. The inventionconsists in improvements designed, among other things, to facilitatevaporization of the fuel and the quick starting of the burner from acold condition-and to make provision tending to prevent the accumulationof unconsumed carbon in the fuel spaces, while permitting the readyclearing from the fuel spaces of any such accumulations. For descriptivepurposes the fuel is herein referred. to as oil, although other forms ofliquid fuel may be employed.

The invention will be best understood by reference to the followingdescription when taken in connection with the accompanying drawings,while its scope will be'more particularly pointed out in the appendedclaims.

In the drawings:

Fig. 1 is a plan view, partly broken away, showing a burner embodyingone form of the invention;

Fig. 2 is a central, sectional elevation, partly broken away, of theburner shown in Fig. 1, the section being taken on the line 22 in Fig.1; v ig. 3 isa similar section, taken on the line 3-3 in Fig. 1; i

Fig. 4 is a plan view similar to Fig. 1, showing a modified form of theinvention;

Fig. 5 is a section similar to Fig. 2 taken on the line 55 in Fig. 4; I

Fig. 6 is a perspective of the removable vaporizing plate employed inthe burner shown in Figs. 1, 2 and 3;

Fig. 7 is a side elevation of the va orizing bottom and cover platesemploye in the burner shown in Figs. 4 and 5; and

Fig. 8 is a detail, on a larger scale, showing a connection between thevaporizing bottom and cover plates of Fig. 7.

Referring to thedrawings (Figs. 1, 2 and 3) and to the type of burner towhich, for illustrative purposes, one form of the invention is thereshown applied, the burner is of the so-called combustion tube type havina cast iron base 11 supported in any suitable wall 33 and 1931.. SerialNo. 532,648..

manner and having on its under side a boss 13 for the attachment of afuel supply pipe 15. The base plate comprises an outer annular plate 17and an inner annular concentric plate 19 connected one to the other by aseries of webs 21 (Fig. 1), herein four in number, and providing for anannular air admission space 23 between the plates, interrupted only bythe webs 21.

The outer plate is provided with spaced, annular, upstanding walls 25and 27 forming between them a fuel space, herein in the form of arelatively narrow, annular channel or groove 29. The inner plate isprovided with similar walls 31 and 33 forming between them a relativelybroad fuelspace 35 in the form of an annular channel of greater radialwidth than the channel 29, there being provided fuel supply ducts 37 inthe webs 21 connecting the inner and outer fuel spaces. A central airsupply opening 39 is formed in the b0ttoniil of the base within theinner upstanding wa The top of the inner broadened fuel space is closedin part by a removable cover plate 1 41 seated on the top of the innerflange or having a down-turned lip fitting within the flange andpositioning the cover plate thereon. The walls of the cover plate extendoutwardly over the fuel space 35, terminating in a down-turned flangeand an outwardly turned lip, which latter is spaced from the oppositewall 31 of the fuel space to provide a fuel or vapor groove underl ingthe overhead combustion chamber an an annular exit slot for the passageof vaporized oil into the combustion chamber. 1

An inner combustion chamber aligning with the annular exitslot is formedbetween the combustion tubes 43 and 45, the latter being in the form ofperforated sheet metal cylinders, the tube 43 being seated on theoutturned lip of the removable cover 41 and the tube 43 on the outershoulderof the annular wall 31. Another combustion chamber aligning withthe outer fuel groove 29 is formed between similar combustion tubes 47and 49 seated respectively on the shouldered edges of the upstandingwalls 27 and 25.

There is thus formed an inner air chamber 51 enclosed within thecombustion tube 43 to which air is supplied through the central opening39 in the base and an intermediate air chamber 53 between the combustiontubes 47 and '49 to which air is supplied through the annular opening23. The inner air chamber is closed by the plate 55 res'tin on the topof the tube 43 and the interm 'ate air chamber by a plate 5? resting onthe tops of the tubes 45 and 47, these plates leaving annular exitpassages for the products of combustion from the two combustionchambers.

It will be observed that oil is supplied through the pipe 15 and theinner fuel chamber near the inner covered part thereof, the coveredportion functioning as a vaporizing space in which, during the normalestablished operation of the burner, the oil is vaporized and fromwhichit passes in vaporized form into the uncovered portion of the a fuelspace and thence into the overhead combustion chamber between the tubes43 and 45, and also passes in vaporized form through the ducts 37 intothe outer fuelor va or groove 29 and the outer combustion cham r betweenthe tubes 47 and'49.

In the described form of burner, to hasten the initial vaporization ofthe oil and facilitate the cleaning of the vaporized space, specialprovision is made for the vaporizing space comprising an oil-receiving,heat-conducting lining and a vaporizing cover plate 41 of particularconstruction.

For this purpose the broad fuel channel is provided with a removableannular vaporizing plate 59, presenting a trough-like structure, hereinof the construction shown in Fig. 6. This plate is preferably formed ofthin sheet metal, preferably one-thirtysecond of an inch or less inthickness, and composed of material having a relatively high heatconductivity, such as copper or aluminum. The plate is provided with anouter Lip-turned flange 61 and an inner up-turned flange or lip 63, thedimensions of the struc-' ture being such that it fits the bottom of thechannel beneath the vaporizing space but may be readily slipped intoplace therein or removed therefrom. Where it is desired to employ a wickfor starting the burner, the plate is so dimensioned that whenpositioned in the base it leaves an annular space between the outerflange 61 and the upstanding wall- 31 adapted to contain theasbestosorother wick 65 of the type ordinarily employed for thispurpose.

The vaporizing plate is provided in its bottom ith an opening 67surrounded by a raised lip 69 which, when the plate is in place,

is adapted to register with and seat over the upwardly projecting end ofthe fuel pipe 15, so that all the liquid oil is delivered onto thebottom of the vaporizing plate.

To permit the oil to saturate the wick preliminarily to starting theburner, the outer supply ducts 37, so that the oil vapor may 70 passwithout hindrance to the outer fuel grooves 29, the wick being also cutaway where it overlies the mouths of such ducts.

In the operation of the burner, the latter is preliminarily heatedeither by igniting the wick 65 which is first saturated with oiladmitted through the supply pipe 19, or by means of a priming fluidalone placed in the fuel space, or in any other desired malinei. Oil isadmitted through the supply pipe under the regulation of any of theusual feeding devices. These commonly provide for the flow of oil from afeeding device at some definite level which may be accurately regulatedso that the flow of oil may be maintained at an approximatelypredetermined level over the bottom of the vaporizing plate and a flowthereby maintained ofrelatively shallow depth, spreading over the platein a more or less film like form. Such regulating devices may be of theusual or common construction and are not herein shown.

As soon as the combustion gets under way, a the combustion tubes soonbecome red hot and the central air chamber 51 which is en- 9 closed bythe walls'of the inner combustion tube becomes highly heated. The coverplate 41 (shown'of exaggerated thickness in the drawings) is preferablyformed of thin sheet metal, such as chromium steel, and preferably aboutone-thirtysecond of an inch or less in thickness. A suitable alloy forthe cover plate may be had by using a chrome steel containing from 16%to 18% of chrome.

Such a cover plate is thereby adapted to heat 1 rapidly from the heattransmitted from the combustion chamber and conducted to the cover platefrom the inner chimney 43, as well as by conduction and radiation fromthe inner air chamber which the cover plate underlies and to which itsupper surface is exposed. The thin sheet metal cover plate thereforetakes up and acquires almost instantly the heat from the inner chimneyand the inner air chamber and quickly becomes red hot, reflecting theheat against the adjoining walls of the underlying vaporizing plate 59and upon any liquid oil flowing over the surface thereof. The vaporizingplate itself, being of high conductivity, transmits rapidly to the oilheat received from the coverplate and from the adjoining walls of thebase, so that by the joint action of the cover plate and the vaporizingplate "aporization of the oil starts quickly throughout the vaorizi'ngspace soon after the combustion is initiated and continues with stillgreater effectiveness and efficiency as the combustion proceeds.Accordingly, early in the starting period of the burner, vaporizationtakes place i the down-turned flange wholly in the vaporizing s acewhich is formed by the broad, covere inner part of the cham er 35, theoil passing in vaporized form into the outer part of. the fuel space andthrough the ducts into the outer fuel roove .to be burned in thecombustion chamrs communicating therewith. By constructing the coverplate of thin sheet metal, it is not only adapted efliciently to radiateand reflect the heat from the air chamber and combustion chamber to thevaporizin chamber, but it may be made in the form 0 a stamping fittingthe base more accurately than a casting and restricting less of thecross-sectional area of the central air opening 11 and the fuel spaceswhich it covers, thereby increasing the underlying available spacewhich, in the course of long continued'use, may be subject toaccumulations of unconsumed carbon. Being'formed of a non-oxidizablealloy, such as chrome steel, the cover plate is capable of withstandingintense heat without burning out and without oxidization and requires nocleaning.

It will be observed that in the normal operation of the burner,vaporization of the oil takes place wholly in the broad inner channeland on the vaporizing plate 59, liquid oil being delivered directlythrough the bottoni of that plate sothat it spreads thereover in arelatively thin film. Any accumulations of unconsumed carbon, therefore,form on the vaporizing plate itself, which is so constructed that it maybe readily withdrawn and removed from the groove or channel by liftingout the cover plate 41 and inner chimney 43, permitting it to be cleanedwhile removed from the burner or to be discarded, if desired, andreplaced by another similar va orizing plate.

is construction rovi'des an oil receiving, vaporizing cham r lined orfitted with a removable thin sheet metal vaporizing plate of highconductivity and adapted to effectively vaporize the oil through thejoint action of the heat-conducting cover plate.

Referring to the modification of the invention shown in Figs. 4, 5, 7and 8, the vaporizing plate 72 is similarly constructed of thinheat-conducting metal and is in the form of a channel having a widthsubstantially the widthof the covered portion of the vaporizingchamber'and removably fitted into the inner part of that chamber. Theplate is provided with an out-turned flange 73 which is spaced from butunderlies the outturned peripheral lip or flange 75 of the cover plate77, the latter being formed of thin sheet metal similar to the coverplate 41. The flange 73 of the vaporizing plate is cut away at intervalsto provide recesses 79, herein three in number, adapted to receive eacha depending tongue 81 secured to the side of of the cover plate by anysuitable means, as by being spot welded thereto. Between successiverecesses 79 the flange 73 'of the vaporizing plate is struck up topresent an upstanding tongue 83 constituting a spacing member betweenthe two plates. The depending tongues 81 are provided with notches 85 ofa width suitable to receive the walls of the flange 73. The coverplatemay therefore be applied to the vaporizing plate so that its flangerests on the spacing tongues 83 with the tongues 81 enterin the recesses79, and when in that position given a partial turn which will lock thenotched tongues into the opposing edges of the flange 73, securin thecover plate to the vaporizing plate, which structure thus integrallyjoined may be placed in that position on the burner base. The outerwalls of the vaporizing plate are preferably provided with a pluralityof apertures 87, serving the same function as the apertures 71 in thevaporizing plate 59, permitting an overflow of oil to saturate the wickin the startin of the burner and the escape of vaporizer? oil to theouter roove 29, while confining the liquid oil in t e vaporizing plateduring the normal operation of the burner. 1

The connecting tongues between the cover plate and the vaporizin latenot only perinit the two to be instaled and removed as a single piece,but also to provide a heat-conductive connection or contact between thecover, plate and the vaporizing plate, acceleratin the heatin of thelatter.

While I have erein shown and described for the purpose of illustrationone specific embodiment of the'invention as applied to one particulartype of burner, it is to be understood that the details of constructionmay be varied within .wide limits and that the invention has applicationto widely var n'g t pes of burners, all without departing rom the s iritthereof. 1

I c aim:

"1. A burner havin pairs of spaced, concentric, annular, comfimstiontubes forming spaced, inner and outer combustion chambers with anintermediate air chamber and inner air chamber enclosed by the innercombustion tube, a base having s aced, annular, upstanding wallspresenting etween them concentric, spaced, inner and outer fuel chambersunderlying and communicating each with,one of said combustion chambers,the inner one of said fuel chambers being of greater width than theouter chamber, said base having openings one into each of said airchambers,

a removable thin sheet metal cover overlying and covering a part of thewider fuel cham. ber near one annular upstanding wall thereof butproviding an uncovered opening near the opposite upstanding wallthereof, said opening registering with the inner combustion chamber andsaid cover underlying a part of one of said air chambers, a vaporizingmember compnslng a l1qu1d-fuel-rece1v1ng, thin sheet-metal,heat-conducting structure in the covered part of said wider fuelchamber, means for delivering liquid fuel to said vaporizing member, anda fuel supply duct connecting said inner and outer channels.

, 2. A combustion tube burner having a base provided with inner andouter fuel chambers, the inner chamber being broadened to provide avaporizing space, inner and outer, spaced, perforated walls formingbetween them a plurality of combustion chambers in communication withandupstanding relation one above each of said fuel chambers, and

forming also an intermediate air chamber between the combustion chambersand an inner air chamber within the inner combustion chamber, a walloverlying and covering a part of the inner fuel chamber but leaving arela-' tively narrow aperture at the outer side thereof opening into theoverhead combustion chamber, said, wall underlying one of said airchambers between the latter and the inner fuel chamber, a vaporizingmember comprising a liquid-fuel-receiving, thin sheet-metal,heat-conducting structure in said broadened inner chamber, means fordelivering liquid fuel to said member, and a fuel supply connectionbetween the two fuel chambers.

3. A burner havin a pair of concentric, spaced, annular com ustion tubesforming between them a combustion chamber and'havin g an inner airchamber enclosed by the inner combustion tube, a'base having spaced,annular, upstanding walls presenting between them a broad, annular, fuelchamber, a re movable heat-conducting cover plate covering a part ofsaid fuel chamber near the inner,

annular wall thereof and underlying a part of said inner air chamber butproviding an uncovered opening in said channel adiacent the outer,annular wall thereof, said opening registering with said combustionchamber, a

vaporizer comprising a liquid-fuel-receiving, thin sheet-metal,heat-conducting member in said channel beneath said cover plate, andmeans fordelivering liquid fuel to said member. Y

4. In a liquid fuel burner, a base having spaced, upstanding, inner andouter walls which provide between them a wide fuel chamber, a capremovably seated on the top of said inner wall and extending over thetop of said wide chamber but providing between it and said outer wall arelatively narrow opening for said chamber, spaced combustion tubescarried by said cap and said outer wall in surrounding relation withsaid opening and upstanding thereabove, a vaporizer comprising aliquid-fuel-receiving, thin sheet-metal, heat-conducting member in saidchamber be neath said cap, and means for. delivering liquid fuel to saidmember.

5. A combustion tube burner having a combustion chamber, a base providedwith a vapor groove underlying said chamber,

the latter, a removable li uid-fuel-receiving,

thin sheet-metal, heat-con ucting member for said vaporizing space, anda removable heatconducting cover for the vaporizing space underlyingsaid inner air chamber.

7. 'A combustion tube burner having a base provided with an annular fuelchannel, combustion tubes supported by the base forming between them acombustion chamber in upstanding relation to the fuel chamber andcommunicating therewith, an annular, liquid fuel vaporizing member ofthin heat-conductmg, sheet-metal in said fuel channel and freelyremovable therefrom on the removal of the combustion tubes from thebase, and means for delivering liquid fuel to said vaporizing member.

8. A combustion tube burner having a combustion chamber, a burner basehaving a fuel channel beneath and communicating with the combustionchamber, and a vaporizing member in said channel comprising aliquid-fuelreceiving, thin sheet-metal structure of heatconductingmaterial, said member being of lesser width'than the channel and proiding for a wick space in said channel beneath the combustion chamber.

9. A combustion tube burner having a base provided with inner and outerfuel channels,

a fuel supply duct connectin said channels, a vaporizing member in saiinner channel comprising a thin sheet-metal, trough-like structureofheat-conducting material removably seated in the channel, said structurehaving-one or more openings in its side and having aliquid-fuel-receiving opening in its bottom, and means for deliveringliquid fuel to the inner channel on said vaporizing structure.

10. A burner having a pair of concentric, spaced, annular, combustiontubes forming between them a combustion chamber and having an inner airchamber enclosed by the inner combustion tube, a base having upstandingwalls presenting between them a broad, annular fuel chamber, a removablethin sheetmetal, heat-conducting cover plate covering the inner part ofsaid fuel chamber and underlying the inner air chamber and providingafuel vaporizing'spaee thereunder but leaving 'an uncovered openingadjacent the outer wall head combustion chamber, and means fordelivering liquid fuel to the fuel chamber.

11, A combustion tube burner havin a combustion chamber, a base having auel vapor space beneath and communicating with the combustion chamber, avaporizing space communicating with the fuel vapor space, a removablecover plate for the vaporizing space, a vaporizing member comprising aliquid-fuel-receiving, thin sheet-metal, heatconducting structure in thevaporizing space, means connecting the vaporizing member to the cover,and means for supplying liquid fuel to the vaporizing member. Intestimony whereof, I have signed my name to this specification.

FREDERICK F. NEUMANN.

